1. Field of the Invention
The present invention relates to a flexible solar cell including a photoelectric conversion layer which is disposed on a flexible substrate and is constituted by a laminated layer of non-single crystalline silicon thin films.
2. Description of the Related Art
Solar cells have been vigorously developed as electric power resources for promoting saving energy. Among the solar cells, a solar cell including a photoelectric conversion layer constituted by mainly laminating non-single crystalline silicon thin films such as amorphous films, microcrystalline films, and polycrystalline films has a feature that it can be manufactured at low cost.
There is also known a flexible solar cell formed by using mainly an amorphous silicon thin film as a photoelectric conversion layer and using a flexible substrate.
Since a flexible solar cell is light in weight and can be freely bent, such application is conceivable that the solar cell is used to be stuck to clothes, a tent, or the like.
As a substrate having flexibility used for the flexible solar cell, in addition to a resin substrate of PET (polyethylene terephthalate), PEN (polyethylene naphthalate), polyimide, PES (polyether sulfide), or the like, a metal substrate of stainless is used.
The stainless substrate has merits that a substrate having strength such as tensile strength, which is higher than that of the resin substrate, can be obtained at low cost.
However, when the stainless substrate is used, there has been a case in which problems occur such that deformation is caused in the manufacturing steps, or a flexible solar cell after the manufacture is warped to the substrate side so that sticking to a flat region becomes difficult, and the solar cell looks unattractive as commodities.